Nonparametric modeling of high--frequency VOR responses during post--operative recovery following ablative unilateral labyrinthine surgery was used to track adaptive changes of the VOR during compensation. A study of 19 patients classified as having panic disorder were shown to have abnormal VOR responses at higher, behaviorally significant frequencies tested with the VAT. The results showed a highly significant correlation between panic--prone patients and vestibular disorders. A study of 14 general anxiety disorder patients showed significantly less VOR abnormalities than the panickers. Patients undergoing balance retraining therapy are tested periodically before, during and following therapy in order to compare objective changes with baseline results. Nonparametric gains and phases assist the therapist in setting the pace and scale of exercise regimens. Our results show that extensive damage to inner--ear hair cells, resulting from an extended treatment course of gentamicin antibiotic for a non--inner--ear infection, can be objectively documented during baseline (pre--therapy) testing by both the nonparametric and parametric results. A series of 23 patients with documented gentamicin ototoxicity all produced an unusual gain--phase pattern that is useful for identifying this disorder. Of equal importance are our results that patients with severe bilateral labyrinthine damage can show dramatic objective improvements in their VOR responses, provided that they follow specific courses of therapy.